After forming two right triangles, which right triangle theorem did you have to use twice to solve for side lengths that were not in the final equation?

The Pythagorean theorem relates the side lengths of a right triangle: a² + b² = c². After forming two right triangles, you would use this theorem in each triangle to find the side lengths needed for the final equation, even though those lengths do not appear in that equation. The correct choice is the Pythagorean theorem.

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